In the packaging and marketing of a variety of food products, such as bakery goods, cheeses, meats, and cereals, difficulty has been experienced in the insertion of various promotional pieces such as coupons, recipes, collection cards, or other types of printed inserts. Numerous problems are presented when food oils contact the printing ink. As a result, the Food & Drug Administration allows only a small number of vegetable-based inks to be used in materials that are in direct contact with food. This limits the scope of applications for promotional pieces because the food product must be protected from ink or odor contamination coming from the promotional piece even in situations where the vegetable-based inks are used. Further, the promotional piece must be protected as well from absorbing moisture or grease from the product. This is because a printed promotional piece that is soiled has the potential of imparting contamination to the product. Also, a printed promotional piece that is stained, particularly a collection card, is counterproductive to the original purpose of the promotion.
In the past, most promotional pieces were printed on paper or paperboard. The only way to overcome the ink contamination problem with these types of pieces was to over-wrap the pieces. This entails placing the piece or insert in a bag of a transparent plastic, such as cellophane, and sealing it. Unfortunately over-wrapping presented some major problems:
1. Over-wrapping is costly, in many cases doubling the cost of the promotion.
2. The contract packaging company who does the over-wrapping dictates the schedule.
3. Machines that insert the pieces into the package were not made for over-wrapped pieces, and results of this mismatch include a large waste factor due to dispenser malfunction because of the over-wrap, pillowing, hang-ups on the back seal, and static build-up causing mis-feeds.
To overcome these problems, there was an attempt at developing another type of piece which was constructed of printed paper with a polypropylene film laminated to it. This achieved the desired savings in cost by eliminating the over-wrap and protecting the food from ink contact, but this structure has very poor product resistance. In most applications, the moisture from oils and food products seeped into the paper, causing stains and actually delaminating the insert. The result was a very unattractive promotion piece that exposed the inks and adhesive to the food products. This problem is known as wicking and has the potential to occur in most products where promotional pieces or inserts are used. Examples of some of the prior art arrangements discussed herein are illustrated and described in U.S. Pat. Nos. 1,849,774, 1,924,903, 2,225,694, 2,255,810, 2,578,150, 2,596,514, 2,911,305, and 3,373,045.
Another insert construction that has been developed to be utilized as a promotional piece or in-pack insert is illustrated and described in U.S. Pat. No. 4,837,956, which is incorporated herein by reference. In this insert construction, a plastic film laminate insert is disclosed in which a core layer of polymeric film is printed on one or both sides with a desired message. The ink on each side of the core layer is coated with an adhesive over which is applied a transparent and grease-resistant polymeric film that encloses and seals the printing ink against any potential contaminants, such as a grease, oil or other moisture which may emanate from the food product.
Due to the monolithic construction of this insert, the insert is limited to a single insert or coupon structure. Because a large number of products have the capability of accepting inserts of this type, it is desirable to provide more than one insert on many occasions. However, as it is unwieldy to place multiple inserts in a single package for various reasons, it is desirable to develop an insert that has the capability of forming multiple inserts in a single structure.